He was formerly a director at the bakery giant, established by his father in the 1930s.

In the 1970s, he worked as a children’s officer with social services before becoming a teacher.

While teaching, he launched the Greggs Children's Cancer Run , after a pupil was diagnosed with kidney cancer and given a 30 per cent chance of survival.

The first of the historic allegations dates from January 1963, where it is alleged Gregg sexually abused a 12-year-old boy in a swimming pool.

The other allegations are said to have taken place between 1988-91, at locations including Gregg’s home gymnasium.

The accusations relate to boys aged between 11 and 14.

Prosecution Paul Greaney QC told Leeds Crown Court: “On the surface, he has lived a life of decency, indeed one of distinction.

"He is a married man with two grown up daughters and grandchildren. He is a wealthy and successful businessman and a charity fundraiser on a large scale.

“Furthermore he has spent much of his adult life working as a teacher, headmaster and children’s social worker.

“As Colin Gregg would have it, he dedicated his life to helping children realise their potential. And so, on the surface, Colin Gregg deserves the respect and thanks of our community.”

But Mr Greaney said beneath the surface Mr Gregg was “an abuser of children”, and during two periods about 20 years apart he engaged in the sexual abuse of boys, “always acting in breach of trust”.

The jury heard Gregg has faced allegations of sexual misconduct against boys in the past, but was not convicted.

Mr Greaney said: “It is the position of the prosecution that Colin Gregg has concealed his true nature beneath a veneer of respectability during his adult life and indeed, as we shall soon set out, it is, moreover, the prosecution case that he has exploited his position in society to perpetrate abuse.”

Between 1967-70, Gregg worked in the family business. His father, John Gregg, founded the famous and successful bakery chain.

Gregg taught at Durham School, a school in Newcastle’s west end before moving to Newcastle City Council’s children’s department as a social worker. He then became the headmaster at Tynemouth King’s School.

In 1989, Gregg became the director of children’s charity the Yellow Brick Road Fund.

During this time he operated a running club from his home at Homefarm Steading, Gosforth.

The jury was told Gregg stood trial in 1997 accused of indecently assaulting a boy while he was aged 10-14.

Gregg was acquitted at Newcastle Crown Court.

Mr Greaney said the allegations carry “hallmarks of his behaviour” across the years and across the two sets of complainants.

The allegations are “mutually supportive of each other”, according to the prosecution.

It's claimed the evidence from the original trial shows Gregg finds young boys physically attractive and he has a tendency to act on that attraction.

There are nine charges from four complainants, though the court will hear from six witnesses.

Prosecutors allege the boys suffered “disturbing abuse at the hands of someone they were entitled to trust”.

The first complainant, now in his 60s, claims Gregg sexually assaulted when he was aged 13 while he was at boarding school.

He told the jury: “It occurred in the swimming pool during a swimming lesson. I was in the pool, Mr Gregg approached me saying that he could improve my breast stroke by holding my legs.

“At that point I had my legs around his waist. At some point I realised that his hand moved inside my swimming trunks.”

At the time Gregg was involved with the charity TOC H, a Christian charity.